Publications by authors named "Fabricio C Machado"

Malignant melanoma is the main cause of death in patients with skin cancer. Overexpression of Proteolipid protein 2 (PLP2) increased tumor metastasis and the knockdown of PLP2 inhibited the growth and metastasis of melanoma cells. In the present work, we studied the antitumor activity of peptide Rb4 derived from protein PLP2.

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The cyclic VHCDR3-derived peptide (Rb9) from RebMab200 antibody, directed to a NaPi2B phosphate-transport protein, displayed anti-metastatic melanoma activity at 50-300 μg intraperitoneally injected in syngeneic mice. Immune deficient mice failed to respond to the peptide protective effect. Rb9 induced increased CD8+ T and low Foxp3+ T cell infiltration in lung metastases and high IFN-γ and low TGF-β in lymphoid organs.

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Some 1,3-diarylureas and 1-((1,4-trans)-4-aryloxycyclohexyl)-3-arylureas (cHAUs) activate heme-regulated kinase causing protein synthesis inhibition via phosphorylation of the eukaryotic translation initiation factor 2 (eIF2) in mammalian cancer cells. To evaluate if these agents have potential to inhibit trypanosome multiplication by also affecting the phosphorylation of eIF2 alpha subunit (eIF2α), we tested 25 analogs of 1,3-diarylureas and cHAUs against Trypanosoma cruzi, the agent of Chagas disease. One of them (I-17) presented selectivity close to 10-fold against the insect replicative forms and also inhibited the multiplication of T.

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interacts with host cells, including cardiomyocytes, and induces the production of cytokines, chemokines, metalloproteinases, and glycan-binding proteins. Among the glycan-binding proteins is Galectin-3 (Gal-3), which is upregulated after infection. Gal-3 is a member of the lectin family with affinity for β-galactose containing molecules; it can be found in both the nucleus and the cytoplasm and can be either membrane-associated or secreted.

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Host actin cytoskeleton polymerization has been shown to play an important role during Trypanosoma cruzi internalization into mammalian cell. The structure and dynamics of the actin cytoskeleton in cells are regulated by a vast number of actin-binding proteins. Here we aimed to verify the impact of AFAP-1L1, during invasion and multiplication of T.

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Histones are well-conserved proteins that form the basic structure of chromatin in eukaryotes and undergo several post-translational modifications, which are important for the control of transcription, replication, DNA damage repair, and chromosome condensation. In early branched organisms, histones are less conserved and appear to contain alternative sites for modifications, which could reveal evolutionary unique functions of histone modifications in gene expression and other chromatin-based processes. Here, by using high-resolution mass spectrometry, we identified and quantified histone post-translational modifications in two life cycle stages of Trypanosoma cruzi, the protozoan parasite that causes Chagas disease.

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The trypanosome life cycle consists of a series of developmental forms each adapted to an environment in the relevant insect and/or mammalian host. The differentiation process from the mammalian bloodstream form to the insect-midgut procyclic form in Trypanosoma brucei occurs in two steps in vivo. First proliferating 'slender' bloodstream forms differentiate to non-dividing 'stumpy' forms arrested in G1.

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Trypanosoma cruzi has high biological and biochemical diversity and variable tissue tropism. Here we aimed to verify the kinetics of cytokine and chemokine in situ secretion in animals infected with two distinct T. cruzi strains after oral inoculation.

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Chagas disease, which is caused by the parasite Trypanosoma cruzi, is an important cause of cardiomyopathy in Latin America. It is estimated that 10%-30% of all infected individuals will acquire chronic chagasic cardiomyopathy (CCC). The etiology of CCC is multifactorial and involves parasite genotype, host genetic polymorphisms, immune response, signaling pathways and autoimmune progression.

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The seasonal chemical composition of essential oils from Inga laurina was determined by GC/MS. In the stem bark's essential oil extracted during the dry season, the presence of terpenoids (30.05%) stood out, and phytol (9.

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Structural studies of proteins normally require large quantities of pure material that can only be obtained through heterologous expression systems and recombinant technique. In these procedures, large amounts of expressed protein are often found in the insoluble fraction, making protein purification from the soluble fraction inefficient, laborious, and costly. Usually, protein refolding is avoided due to a lack of experimental assays that can validate correct folding and that can compare the conformational population to that of the soluble fraction.

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The invasion of host cells by the intracellular protozoan Trypanosoma cruzi requires interactions with host cell molecules, and the replication of the parasite requires escape from a parasitophorous vacuole into the host cell cytosol. Galectin-3, a member of β-galactosidase-binding lectin family, has numerous extracellular and intracellular functions. In this study, we investigated the role of galectin-3 during the invasion and intracellular trafficking of T.

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The chemical composition of the essential oils from leaves, bark and wood of Cassia bakeriana Craib. was determined by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). Alcohols, aldehydes and fatty acids were the major components in leaf and bark oil, while wood essential oil was rich in fatty acids.

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Background: P21 is a secreted protein expressed in all developmental stages of Trypanosoma cruzi. The aim of this study was to determine the effect of the recombinant protein based on P21 (P21-His(6)) on inflammatory macrophages during phagocytosis.

Findings: Our results showed that P21-His(6) acts as a phagocytosis inducer by binding to CXCR4 chemokine receptor and activating actin polymerization in a way dependent onthe PI3-kinase signaling pathway.

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